UFCThe Ultimate Fighting Championship (UFC) is a U.S.-based mixed martial arts organization, recognized as the largest MMA promotion in the world. The UFC is headquartered in Las Vegas, Nevada and is owned and operated by Zuffa, LLC. This promotion is responsible for solidifying the sport's postion in the history-books.
UFC is currently undergoing a remarkable surge in popularity, along with greater mainstream media coverage. UFC programming can now be seen on FOX, FX, and FUEL TV in the United States, as well as in 35 other countries worldwide.

B/c RAmpage talked mad shit about Wandy, and always called him ugly, talked about how he's gonna knock him out, etc. Then, after Rampage beat someone(forget who) he called out Wandy saying to give him "his belt" which resulted in Wandy coming in and saying "MAH BELT" and pushing him all crazy-roidrage-like.

It was after he beat Kevin Randleman.
It's just a general lack of respect, as people have said like calling him ugly. Disrespecting him after his 1st win....talking on a cell phone during the Brazilian national anthem.....i thought that was just awful

edit: I just watched that vid of him cursing at Wanderlei and what not and that is more than enough reason for Wandy not to like Rampage. But what hurt worse those words or the knees that had Rampage teetering between the ropes...But I don't know when that video was made and in his latest interview Rampage was clearly nothing like that.